2019-09-13 19:41:29

by Pascal van Leeuwen

[permalink] [raw]
Subject: [PATCHv2 2/3] crypto: inside-secure - Add support for the Chacha20-Poly1305 AEAD

This patch adds support for the Chacha20-Poly1305 cipher suite.
It adds both the basic rfc7539(chacha20,poly1305) as well as the
rfc7539esp(chacha20,poly1305) variant for IPsec ESP acceleration.

changes since v1:
- rebased on top of DES changes done to cryptodev/master

Signed-off-by: Pascal van Leeuwen <[email protected]>
---
drivers/crypto/inside-secure/safexcel.c | 2 +
drivers/crypto/inside-secure/safexcel.h | 8 +
drivers/crypto/inside-secure/safexcel_cipher.c | 276 ++++++++++++++++++++++---
3 files changed, 262 insertions(+), 24 deletions(-)

diff --git a/drivers/crypto/inside-secure/safexcel.c b/drivers/crypto/inside-secure/safexcel.c
index f958c92..b81f0bc 100644
--- a/drivers/crypto/inside-secure/safexcel.c
+++ b/drivers/crypto/inside-secure/safexcel.c
@@ -1174,6 +1174,8 @@ static int safexcel_request_ring_irq(void *pdev, int irqid,
&safexcel_alg_xcbcmac,
&safexcel_alg_cmac,
&safexcel_alg_chacha20,
+ &safexcel_alg_chachapoly,
+ &safexcel_alg_chachapoly_esp,
};

static int safexcel_register_algorithms(struct safexcel_crypto_priv *priv)
diff --git a/drivers/crypto/inside-secure/safexcel.h b/drivers/crypto/inside-secure/safexcel.h
index c7f1a20..282d59e 100644
--- a/drivers/crypto/inside-secure/safexcel.h
+++ b/drivers/crypto/inside-secure/safexcel.h
@@ -373,6 +373,7 @@ struct safexcel_context_record {
#define CONTEXT_CONTROL_CRYPTO_ALG_XCBC128 (0x1 << 23)
#define CONTEXT_CONTROL_CRYPTO_ALG_XCBC192 (0x2 << 23)
#define CONTEXT_CONTROL_CRYPTO_ALG_XCBC256 (0x3 << 23)
+#define CONTEXT_CONTROL_CRYPTO_ALG_POLY1305 (0xf << 23)
#define CONTEXT_CONTROL_INV_FR (0x5 << 24)
#define CONTEXT_CONTROL_INV_TR (0x6 << 24)

@@ -385,6 +386,7 @@ struct safexcel_context_record {
#define CONTEXT_CONTROL_CRYPTO_MODE_CTR_LOAD (6 << 0)
#define CONTEXT_CONTROL_CRYPTO_MODE_XTS (7 << 0)
#define CONTEXT_CONTROL_CRYPTO_MODE_XCM ((6 << 0) | BIT(17))
+#define CONTEXT_CONTROL_CHACHA20_MODE_CALC_OTK (12 << 0)
#define CONTEXT_CONTROL_IV0 BIT(5)
#define CONTEXT_CONTROL_IV1 BIT(6)
#define CONTEXT_CONTROL_IV2 BIT(7)
@@ -397,6 +399,10 @@ struct safexcel_context_record {
#define EIP197_XCM_MODE_GCM 1
#define EIP197_XCM_MODE_CCM 2

+#define EIP197_AEAD_TYPE_IPSEC_ESP 2
+#define EIP197_AEAD_IPSEC_IV_SIZE 8
+#define EIP197_AEAD_IPSEC_NONCE_SIZE 4
+
/* The hash counter given to the engine in the context has a granularity of
* 64 bits.
*/
@@ -861,5 +867,7 @@ int safexcel_hmac_setkey(const char *alg, const u8 *key, unsigned int keylen,
extern struct safexcel_alg_template safexcel_alg_xcbcmac;
extern struct safexcel_alg_template safexcel_alg_cmac;
extern struct safexcel_alg_template safexcel_alg_chacha20;
+extern struct safexcel_alg_template safexcel_alg_chachapoly;
+extern struct safexcel_alg_template safexcel_alg_chachapoly_esp;

#endif
diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/crypto/inside-secure/safexcel_cipher.c
index 0bafb14..7f14770 100644
--- a/drivers/crypto/inside-secure/safexcel_cipher.c
+++ b/drivers/crypto/inside-secure/safexcel_cipher.c
@@ -17,6 +17,7 @@
#include <crypto/internal/des.h>
#include <crypto/gcm.h>
#include <crypto/ghash.h>
+#include <crypto/poly1305.h>
#include <crypto/sha.h>
#include <crypto/xts.h>
#include <crypto/skcipher.h>
@@ -43,8 +44,8 @@ struct safexcel_cipher_ctx {

u32 mode;
enum safexcel_cipher_alg alg;
- bool aead;
- int xcm; /* 0=authenc, 1=GCM, 2 reserved for CCM */
+ char aead; /* !=0=AEAD, 2=IPSec ESP AEAD */
+ char xcm; /* 0=authenc, 1=GCM, 2 reserved for CCM */

__le32 key[16];
u32 nonce;
@@ -57,6 +58,7 @@ struct safexcel_cipher_ctx {
u32 opad[SHA512_DIGEST_SIZE / sizeof(u32)];

struct crypto_cipher *hkaes;
+ struct crypto_aead *fback;
};

struct safexcel_cipher_req {
@@ -86,10 +88,24 @@ static void safexcel_cipher_token(struct safexcel_cipher_ctx *ctx, u8 *iv,
} else if (ctx->alg == SAFEXCEL_CHACHA20) {
cdesc->control_data.options |= EIP197_OPTION_4_TOKEN_IV_CMD;

- /* 96 bit nonce part */
- memcpy(&cdesc->control_data.token[0], &iv[4], 12);
- /* 32 bit counter */
- cdesc->control_data.token[3] = *(u32 *)iv;
+ if (ctx->aead == EIP197_AEAD_TYPE_IPSEC_ESP) {
+ /* 32 bit nonce part */
+ cdesc->control_data.token[0] = ctx->nonce;
+ /* 64 bit IV part */
+ memcpy(&cdesc->control_data.token[1], iv, 8);
+ /* 32 bit counter, starting at 0 */
+ cdesc->control_data.token[3] = 0;
+ } else if (ctx->aead) {
+ /* 96 bit nonce part */
+ memcpy(&cdesc->control_data.token[0], iv, 12);
+ /* 32 bit counter, starting at 0 */
+ cdesc->control_data.token[3] = 0;
+ } else {
+ /* 96 bit nonce part */
+ memcpy(&cdesc->control_data.token[0], &iv[4], 12);
+ /* 32 bit counter */
+ cdesc->control_data.token[3] = *(u32 *)iv;
+ }

return;
} else if (ctx->xcm == EIP197_XCM_MODE_GCM) {
@@ -193,12 +209,20 @@ static void safexcel_aead_token(struct safexcel_cipher_ctx *ctx, u8 *iv,
token[13].instructions = EIP197_TOKEN_INS_TYPE_OUTPUT;
}

+ if (ctx->aead == EIP197_AEAD_TYPE_IPSEC_ESP) {
+ /* For ESP mode, skip over the IV */
+ token[7].opcode = EIP197_TOKEN_OPCODE_DIRECTION;
+ token[7].packet_length = EIP197_AEAD_IPSEC_IV_SIZE;
+
+ assoclen -= EIP197_AEAD_IPSEC_IV_SIZE;
+ }
+
token[6].opcode = EIP197_TOKEN_OPCODE_DIRECTION;
token[6].packet_length = assoclen;
+ token[6].instructions = EIP197_TOKEN_INS_LAST |
+ EIP197_TOKEN_INS_TYPE_HASH;

- if (likely(cryptlen)) {
- token[6].instructions = EIP197_TOKEN_INS_TYPE_HASH;
-
+ if (likely(cryptlen || ctx->alg == SAFEXCEL_CHACHA20)) {
token[10].opcode = EIP197_TOKEN_OPCODE_DIRECTION;
token[10].packet_length = cryptlen;
token[10].stat = EIP197_TOKEN_STAT_LAST_HASH;
@@ -208,8 +232,6 @@ static void safexcel_aead_token(struct safexcel_cipher_ctx *ctx, u8 *iv,
EIP197_TOKEN_INS_TYPE_OUTPUT;
} else if (ctx->xcm != EIP197_XCM_MODE_CCM) {
token[6].stat = EIP197_TOKEN_STAT_LAST_HASH;
- token[6].instructions = EIP197_TOKEN_INS_LAST |
- EIP197_TOKEN_INS_TYPE_HASH;
}

if (!ctx->xcm)
@@ -224,10 +246,7 @@ static void safexcel_aead_token(struct safexcel_cipher_ctx *ctx, u8 *iv,
token[9].instructions = EIP197_TOKEN_INS_TYPE_OUTPUT |
EIP197_TOKEN_INS_TYPE_CRYPTO;

- if (ctx->xcm == EIP197_XCM_MODE_GCM) {
- token[6].instructions = EIP197_TOKEN_INS_LAST |
- EIP197_TOKEN_INS_TYPE_HASH;
- } else {
+ if (ctx->xcm != EIP197_XCM_MODE_GCM) {
u8 *cbcmaciv = (u8 *)&token[1];
u32 *aadlen = (u32 *)&token[5];

@@ -386,7 +405,7 @@ static int safexcel_aead_setkey(struct crypto_aead *ctfm, const u8 *key,
goto badkey;
break;
default:
- dev_err(priv->dev, "aead: unsupported hash algorithm\n");
+ dev_err(priv->dev, "aead: unsupported hash algorithmn");
goto badkey;
}

@@ -434,6 +453,17 @@ static int safexcel_context_control(struct safexcel_cipher_ctx *ctx,
CONTEXT_CONTROL_DIGEST_XCM |
ctx->hash_alg |
CONTEXT_CONTROL_SIZE(ctrl_size);
+ } else if (ctx->alg == SAFEXCEL_CHACHA20) {
+ /* Chacha20-Poly1305 */
+ cdesc->control_data.control0 =
+ CONTEXT_CONTROL_KEY_EN |
+ CONTEXT_CONTROL_CRYPTO_ALG_CHACHA20 |
+ (sreq->direction == SAFEXCEL_ENCRYPT ?
+ CONTEXT_CONTROL_TYPE_ENCRYPT_HASH_OUT :
+ CONTEXT_CONTROL_TYPE_HASH_DECRYPT_IN) |
+ ctx->hash_alg |
+ CONTEXT_CONTROL_SIZE(ctrl_size);
+ return 0;
} else {
ctrl_size += ctx->state_sz / sizeof(u32) * 2;
cdesc->control_data.control0 =
@@ -2318,18 +2348,12 @@ struct safexcel_alg_template safexcel_alg_ccm = {
},
};

-static int safexcel_skcipher_chacha20_setkey(struct crypto_skcipher *ctfm,
- const u8 *key, unsigned int len)
+static void safexcel_chacha20_setkey(struct safexcel_cipher_ctx *ctx,
+ const u8 *key)
{
- struct safexcel_cipher_ctx *ctx = crypto_skcipher_ctx(ctfm);
struct safexcel_crypto_priv *priv = ctx->priv;
int i;

- if (len != CHACHA_KEY_SIZE) {
- crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
- return -EINVAL;
- }
-
if (priv->flags & EIP197_TRC_CACHE && ctx->base.ctxr_dma) {
for (i = 0; i < CHACHA_KEY_SIZE / sizeof(u32); i++) {
if (ctx->key[i] !=
@@ -2343,6 +2367,18 @@ static int safexcel_skcipher_chacha20_setkey(struct crypto_skcipher *ctfm,
for (i = 0; i < CHACHA_KEY_SIZE / sizeof(u32); i++)
ctx->key[i] = get_unaligned_le32(key + i * sizeof(u32));
ctx->key_len = CHACHA_KEY_SIZE;
+}
+
+static int safexcel_skcipher_chacha20_setkey(struct crypto_skcipher *ctfm,
+ const u8 *key, unsigned int len)
+{
+ struct safexcel_cipher_ctx *ctx = crypto_skcipher_ctx(ctfm);
+
+ if (len != CHACHA_KEY_SIZE) {
+ crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+ safexcel_chacha20_setkey(ctx, key);

return 0;
}
@@ -2382,3 +2418,195 @@ struct safexcel_alg_template safexcel_alg_chacha20 = {
},
},
};
+
+static int safexcel_aead_chachapoly_setkey(struct crypto_aead *ctfm,
+ const u8 *key, unsigned int len)
+{
+ struct safexcel_cipher_ctx *ctx = crypto_aead_ctx(ctfm);
+
+ if (ctx->aead == EIP197_AEAD_TYPE_IPSEC_ESP &&
+ len > EIP197_AEAD_IPSEC_NONCE_SIZE) {
+ /* ESP variant has nonce appended to key */
+ len -= EIP197_AEAD_IPSEC_NONCE_SIZE;
+ ctx->nonce = *(u32 *)(key + len);
+ }
+ if (len != CHACHA_KEY_SIZE) {
+ crypto_aead_set_flags(ctfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+ safexcel_chacha20_setkey(ctx, key);
+
+ return 0;
+}
+
+static int safexcel_aead_chachapoly_setauthsize(struct crypto_aead *tfm,
+ unsigned int authsize)
+{
+ if (authsize != POLY1305_DIGEST_SIZE)
+ return -EINVAL;
+ return 0;
+}
+
+static int safexcel_aead_chachapoly_crypt(struct aead_request *req,
+ enum safexcel_cipher_direction dir)
+{
+ struct safexcel_cipher_req *creq = aead_request_ctx(req);
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_tfm *tfm = crypto_aead_tfm(aead);
+ struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
+ struct aead_request *subreq = aead_request_ctx(req);
+ u32 key[CHACHA_KEY_SIZE / sizeof(u32) + 1];
+ int i, ret = 0;
+
+ /*
+ * Instead of wasting time detecting umpteen silly corner cases,
+ * just dump all "small" requests to the fallback implementation.
+ * HW would not be faster on such small requests anyway.
+ */
+ if (likely(req->assoclen > EIP197_AEAD_IPSEC_IV_SIZE &&
+ req->cryptlen >= POLY1305_DIGEST_SIZE)) {
+ return safexcel_queue_req(&req->base, creq, dir);
+ }
+
+ /* HW cannot do full (AAD+payload) zero length, use fallback */
+ for (i = 0; i < CHACHA_KEY_SIZE / sizeof(u32); i++)
+ key[i] = cpu_to_le32(ctx->key[i]);
+ if (ctx->aead == EIP197_AEAD_TYPE_IPSEC_ESP) {
+ /* ESP variant has nonce appended to the key */
+ key[CHACHA_KEY_SIZE / sizeof(u32)] = ctx->nonce;
+ ret = crypto_aead_setkey(ctx->fback, (u8 *)key,
+ CHACHA_KEY_SIZE +
+ EIP197_AEAD_IPSEC_NONCE_SIZE);
+ } else {
+ ret = crypto_aead_setkey(ctx->fback, (u8 *)key,
+ CHACHA_KEY_SIZE);
+ }
+ if (ret) {
+ crypto_aead_clear_flags(aead, CRYPTO_TFM_REQ_MASK);
+ crypto_aead_set_flags(aead, crypto_aead_get_flags(ctx->fback) &
+ CRYPTO_TFM_REQ_MASK);
+ return ret;
+ }
+
+ aead_request_set_tfm(subreq, ctx->fback);
+ aead_request_set_callback(subreq, req->base.flags, req->base.complete,
+ req->base.data);
+ aead_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
+ req->iv);
+ aead_request_set_ad(subreq, req->assoclen);
+
+ return (dir == SAFEXCEL_ENCRYPT) ?
+ crypto_aead_encrypt(subreq) :
+ crypto_aead_decrypt(subreq);
+}
+
+static int safexcel_aead_chachapoly_encrypt(struct aead_request *req)
+{
+ return safexcel_aead_chachapoly_crypt(req, SAFEXCEL_ENCRYPT);
+}
+
+static int safexcel_aead_chachapoly_decrypt(struct aead_request *req)
+{
+ return safexcel_aead_chachapoly_crypt(req, SAFEXCEL_DECRYPT);
+}
+
+static int safexcel_aead_chachapoly_cra_init(struct crypto_tfm *tfm)
+{
+ struct crypto_aead *aead = __crypto_aead_cast(tfm);
+ struct aead_alg *alg = crypto_aead_alg(aead);
+ struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ safexcel_aead_cra_init(tfm);
+ ctx->alg = SAFEXCEL_CHACHA20;
+ ctx->mode = CONTEXT_CONTROL_CHACHA20_MODE_256_32 |
+ CONTEXT_CONTROL_CHACHA20_MODE_CALC_OTK;
+ ctx->hash_alg = CONTEXT_CONTROL_CRYPTO_ALG_POLY1305;
+ ctx->state_sz = 0; /* Precomputed by HW */
+
+ /* Allocate fallback implementation */
+ ctx->fback = crypto_alloc_aead(alg->base.cra_name, 0,
+ CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_NEED_FALLBACK);
+ if (IS_ERR(ctx->fback))
+ return PTR_ERR(ctx->fback);
+
+ crypto_aead_set_reqsize(aead, max(sizeof(struct safexcel_cipher_req),
+ sizeof(struct aead_request) +
+ crypto_aead_reqsize(ctx->fback)));
+
+ return 0;
+}
+
+static void safexcel_aead_chachapoly_cra_exit(struct crypto_tfm *tfm)
+{
+ struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ crypto_free_aead(ctx->fback);
+ safexcel_aead_cra_exit(tfm);
+}
+
+struct safexcel_alg_template safexcel_alg_chachapoly = {
+ .type = SAFEXCEL_ALG_TYPE_AEAD,
+ .algo_mask = SAFEXCEL_ALG_CHACHA20 | SAFEXCEL_ALG_POLY1305,
+ .alg.aead = {
+ .setkey = safexcel_aead_chachapoly_setkey,
+ .setauthsize = safexcel_aead_chachapoly_setauthsize,
+ .encrypt = safexcel_aead_chachapoly_encrypt,
+ .decrypt = safexcel_aead_chachapoly_decrypt,
+ .ivsize = CHACHAPOLY_IV_SIZE,
+ .maxauthsize = POLY1305_DIGEST_SIZE,
+ .base = {
+ .cra_name = "rfc7539(chacha20,poly1305)",
+ .cra_driver_name = "safexcel-chacha20-poly1305",
+ /* +1 to put it above HW chacha + SW poly */
+ .cra_priority = SAFEXCEL_CRA_PRIORITY + 1,
+ .cra_flags = CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_KERN_DRIVER_ONLY |
+ CRYPTO_ALG_NEED_FALLBACK,
+ .cra_blocksize = 1,
+ .cra_ctxsize = sizeof(struct safexcel_cipher_ctx),
+ .cra_alignmask = 0,
+ .cra_init = safexcel_aead_chachapoly_cra_init,
+ .cra_exit = safexcel_aead_chachapoly_cra_exit,
+ .cra_module = THIS_MODULE,
+ },
+ },
+};
+
+static int safexcel_aead_chachapolyesp_cra_init(struct crypto_tfm *tfm)
+{
+ struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
+ int ret;
+
+ ret = safexcel_aead_chachapoly_cra_init(tfm);
+ ctx->aead = EIP197_AEAD_TYPE_IPSEC_ESP;
+ return ret;
+}
+
+struct safexcel_alg_template safexcel_alg_chachapoly_esp = {
+ .type = SAFEXCEL_ALG_TYPE_AEAD,
+ .algo_mask = SAFEXCEL_ALG_CHACHA20 | SAFEXCEL_ALG_POLY1305,
+ .alg.aead = {
+ .setkey = safexcel_aead_chachapoly_setkey,
+ .setauthsize = safexcel_aead_chachapoly_setauthsize,
+ .encrypt = safexcel_aead_chachapoly_encrypt,
+ .decrypt = safexcel_aead_chachapoly_decrypt,
+ .ivsize = CHACHAPOLY_IV_SIZE - EIP197_AEAD_IPSEC_NONCE_SIZE,
+ .maxauthsize = POLY1305_DIGEST_SIZE,
+ .base = {
+ .cra_name = "rfc7539esp(chacha20,poly1305)",
+ .cra_driver_name = "safexcel-chacha20-poly1305-esp",
+ /* +1 to put it above HW chacha + SW poly */
+ .cra_priority = SAFEXCEL_CRA_PRIORITY + 1,
+ .cra_flags = CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_KERN_DRIVER_ONLY |
+ CRYPTO_ALG_NEED_FALLBACK,
+ .cra_blocksize = 1,
+ .cra_ctxsize = sizeof(struct safexcel_cipher_ctx),
+ .cra_alignmask = 0,
+ .cra_init = safexcel_aead_chachapolyesp_cra_init,
+ .cra_exit = safexcel_aead_chachapoly_cra_exit,
+ .cra_module = THIS_MODULE,
+ },
+ },
+};
--
1.8.3.1